21933841 has 4 divisors (see below), whose sum is σ = 21946932. Its totient is φ = 21920752.

The previous prime is 21933839. The next prime is 21933851. The reversal of 21933841 is 14833912.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3478225 + 18455616 = 1865^2 + 4296^2 .

It is a cyclic number.

It is not a de Polignac number, because 21933841 - 2¹ = 21933839 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21933851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3586 + ... + 7531.

It is an arithmetic number, because the mean of its divisors is an integer number (5486733).

Almost surely, 2^21933841 is an apocalyptic number.

It is an amenable number.

21933841 is a deficient number, since it is larger than the sum of its proper divisors (13091).

21933841 is a wasteful number, since it uses less digits than its factorization.

21933841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13090.

The product of its digits is 5184, while the sum is 31.

The square root of 21933841 is about 4683.3578765668. The cubic root of 21933841 is about 279.9227720688.

The spelling of 21933841 in words is "twenty-one million, nine hundred thirty-three thousand, eight hundred forty-one".